On-cell indicators require a user to press one or two buttons, wait for several seconds and then observe an indicator that shows the state of charge of the battery. This is inconvenient for the users because they must remove the batteries from the device, hold the battery and press the button(s). The user must then reinstall the battery into the device. This is cumbersome and time consuming.
Electrochromic displays draw very little power from the cell being tested and can therefore remain on and allow the consumer to just look at the cell to determine the state of charge. However, the current state-of the-art in electrochromic indicator technology has short operational life if it is continuously powered in the on condition. The short operational life could be as short as a few weeks to as long as about a couple of months.
Accordingly, a need exists for improved on-cell indicators.